noun Download 🔗Share An atmospheric phenomenon created by charged particles from the sun striking the upper atmosphere, creating coloured lights in the sky. It is usually named australis or borealis based on whether it is in the Southern or Northern Hemisphere respectively. Examples : "Last winter, my family traveled to Iceland hoping to see the aurora borealis dance across the night sky. " astronomy weather space nature phenomena environment science physics Chat with AIVocabulary GamePractice Reading